<s>
Android	B-Application
software	I-Application
development	I-Application
is	O
the	O
process	O
by	O
which	O
applications	O
are	O
created	O
for	O
devices	O
running	O
the	O
Android	B-Application
operating	I-Application
system	I-Application
.	O
</s>
<s>
Google	O
states	O
that	O
"	O
Android	B-Application
apps	O
can	O
be	O
written	O
using	O
Kotlin	B-Language
,	O
Java	B-Language
,	O
and	O
C++	B-Language
languages	I-Language
"	O
using	O
the	O
Android	B-Application
software	I-Application
development	I-Application
kit	I-Application
(	O
SDK	O
)	O
,	O
while	O
using	O
other	O
languages	O
is	O
also	O
possible	O
.	O
</s>
<s>
All	O
non-Java	O
virtual	O
machine	O
(	O
JVM	B-Language
)	O
languages	O
,	O
such	O
as	O
Go	B-Application
,	O
JavaScript	B-Language
,	O
C	B-Language
,	O
C++	B-Language
or	O
assembly	B-Language
,	O
need	O
the	O
help	O
of	O
JVM	B-Language
language	O
code	O
,	O
that	O
may	O
be	O
supplied	O
by	O
tools	O
,	O
likely	O
with	O
restricted	O
API	O
support	O
.	O
</s>
<s>
Some	O
programming	O
languages	O
and	O
tools	O
allow	O
cross-platform	B-Operating_System
app	O
support	O
(	O
i.e.	O
</s>
<s>
for	O
both	O
Android	B-Application
and	O
iOS	B-Application
)	O
.	O
</s>
<s>
The	O
official	O
Android	B-Application
app	O
distribution	O
mechanism	O
to	O
end	O
users	O
is	O
Google	B-Application
Play	I-Application
;	O
it	O
also	O
allows	O
staged	O
gradual	O
app	O
release	O
,	O
as	O
well	O
as	O
distribution	O
of	O
pre-release	O
app	O
versions	O
to	O
testers	O
.	O
</s>
<s>
The	O
Android	B-Application
software	I-Application
development	I-Application
kit	I-Application
(	O
SDK	O
)	O
includes	O
a	O
comprehensive	O
set	O
of	O
development	O
tools	O
.	O
</s>
<s>
The	O
Android	B-Application
SDK	I-Application
Platform	O
Tools	O
are	O
a	O
separately	O
downloadable	O
subset	O
of	O
the	O
full	O
SDK	O
,	O
consisting	O
of	O
command-line	O
tools	O
such	O
as	O
adb	O
and	O
fastboot	B-Application
.	O
</s>
<s>
The	O
Android	B-Application
Debug	I-Application
Bridge	I-Application
(	O
ADB	O
)	O
is	O
a	O
tool	O
to	O
run	O
commands	O
on	O
a	O
connected	O
Android	B-Application
device	O
.	O
</s>
<s>
Fastboot	B-Application
is	O
a	O
protocol	O
used	O
for	O
flashing	O
filesystems	O
.	O
</s>
<s>
Code	O
written	O
in	O
C/C	O
++	O
can	O
be	O
compiled	B-Language
to	O
ARM	B-Architecture
,	O
or	O
x86	B-Operating_System
native	B-Language
code	I-Language
(	O
or	O
their	O
64-bit	O
variants	O
)	O
using	O
the	O
Android	B-Application
Native	I-Application
Development	I-Application
Kit	I-Application
(	O
NDK	O
)	O
.	O
</s>
<s>
The	O
Android	B-Application
3.1	O
platform	O
(	O
also	O
backported	O
to	O
Android	B-Application
2.3.4	O
)	O
introduces	O
Android	B-Application
Open	O
Accessory	O
support	O
,	O
which	O
allows	O
external	O
USB	O
hardware	O
(	O
an	O
Android	B-Application
USB	O
accessory	O
)	O
to	O
interact	O
with	O
an	O
Android-powered	B-Application
device	I-Application
in	O
a	O
special	O
"	O
accessory	O
"	O
mode	O
.	O
</s>
<s>
When	O
an	O
Android-powered	B-Application
device	I-Application
is	O
in	O
accessory	O
mode	O
,	O
the	O
connected	O
accessory	O
acts	O
as	O
the	O
USB	O
host	O
(	O
powers	O
the	O
bus	O
and	O
enumerates	O
devices	O
)	O
and	O
the	O
Android-powered	B-Application
device	I-Application
acts	O
as	O
the	O
USB	O
device	O
.	O
</s>
<s>
Android	B-Application
USB	O
accessories	O
are	O
specifically	O
designed	O
to	O
attach	O
to	O
Android-powered	B-Application
devices	I-Application
and	O
adhere	O
to	O
a	O
simple	O
protocol	O
(	O
Android	B-Application
accessory	O
protocol	O
)	O
that	O
allows	O
them	O
to	O
detect	O
Android-powered	B-Application
devices	I-Application
that	O
support	O
accessory	O
mode	O
.	O
</s>
<s>
Development	O
tools	O
intended	O
to	O
help	O
an	O
Android	B-Application
device	O
interact	O
with	O
external	O
electronics	O
include	O
IOIO	B-Application
,	O
Android	B-Application
Open	O
Accessory	O
Development	B-Application
Kit	I-Application
,	O
Microbridge	O
,	O
Triggertrap	B-General_Concept
,	O
etc	O
.	O
</s>
<s>
The	O
Android	B-Application
Developer	I-Application
Challenge	O
was	O
a	O
competition	O
to	O
find	O
the	O
most	O
innovative	O
application	O
for	O
Android	B-Application
.	O
</s>
<s>
There	O
is	O
a	O
community	O
of	O
open-source	B-License
enthusiasts	O
that	O
build	O
and	O
share	O
Android-based	O
distributions	O
(	O
i.e.	O
</s>
<s>
firmware	B-Application
)	O
with	O
a	O
number	O
of	O
customizations	O
and	O
additional	O
features	O
,	O
such	O
as	O
FLAC	B-Application
lossless	I-Application
audio	O
support	O
and	O
the	O
ability	O
to	O
store	O
downloaded	O
applications	O
on	O
the	O
microSD	O
card	O
.	O
</s>
<s>
This	O
usually	O
involves	O
rooting	B-Application
the	O
device	O
.	O
</s>
<s>
Rooting	B-Application
allows	O
users	O
root	O
access	O
to	O
the	O
operating	O
system	O
,	O
enabling	O
full	O
control	O
of	O
the	O
phone	O
.	O
</s>
<s>
Rooting	B-Application
has	O
several	O
disadvantages	O
as	O
well	O
,	O
including	O
increased	O
risk	O
of	O
hacking	O
,	O
high	O
chances	O
of	O
bricking	O
,	O
losing	O
warranty	O
,	O
increased	O
virus	O
attack	O
risks	O
,	O
etc	O
.	O
</s>
<s>
It	O
is	O
also	O
possible	O
to	O
install	O
custom	O
firmware	B-Application
,	O
although	O
the	O
device	O
's	O
boot	O
loader	O
must	O
also	O
be	O
unlocked	O
.	O
</s>
<s>
Custom	O
firmware	B-Application
allows	O
users	O
of	O
older	O
phones	O
to	O
use	O
applications	O
available	O
only	O
on	O
newer	O
releases	O
.	O
</s>
<s>
Those	O
firmware	B-Application
packages	O
are	O
updated	O
frequently	O
,	O
incorporate	O
elements	O
of	O
Android	B-Application
functionality	O
that	O
have	O
n't	O
yet	O
been	O
officially	O
released	O
within	O
a	O
carrier-sanctioned	O
firmware	B-Application
,	O
and	O
tend	O
to	O
have	O
fewer	O
limitations	O
.	O
</s>
<s>
CyanogenMod	B-Application
and	O
OMFGB	O
are	O
examples	O
of	O
such	O
firmware	B-Application
.	O
</s>
<s>
On	O
September	O
24	O
,	O
2009	O
,	O
Google	O
issued	O
a	O
cease	O
and	O
desist	O
letter	O
to	O
the	O
modder	O
Cyanogen	O
,	O
citing	O
issues	O
with	O
the	O
re-distribution	O
of	O
Google	O
's	O
closed-source	O
applications	O
within	O
the	O
custom	O
firmware	B-Application
.	O
</s>
<s>
Even	O
though	O
most	O
of	O
Android	B-Application
OS	I-Application
is	O
open	B-License
source	I-License
,	O
phones	O
come	O
packaged	O
with	O
closed-source	O
Google	O
applications	O
for	O
functionality	O
such	O
as	O
the	O
Google	B-Application
Play	I-Application
and	O
GPS	O
navigation	O
.	O
</s>
<s>
Obstacles	O
to	O
development	O
include	O
the	O
fact	O
that	O
Android	B-Application
does	O
not	O
use	O
established	O
Java	B-Language
standards	O
,	O
that	O
is	O
,	O
Java	B-Language
SE	I-Language
and	O
ME	B-Language
.	O
</s>
<s>
This	O
prevents	O
compatibility	O
between	O
Java	B-Language
applications	O
written	O
for	O
those	O
platforms	O
and	O
those	O
written	O
for	O
the	O
Android	B-Application
platform	I-Application
.	O
</s>
<s>
Android	B-Application
reuses	O
the	O
Java	B-Language
language	I-Language
syntax	O
and	O
semantics	O
,	O
but	O
it	O
does	O
not	O
provide	O
the	O
full	O
class	O
libraries	O
and	O
APIs	O
bundled	O
with	O
Java	B-Language
SE	I-Language
or	O
ME	B-Language
.	O
</s>
<s>
However	O
,	O
there	O
are	O
multiple	O
tools	O
in	O
the	O
market	O
from	O
companies	O
such	O
as	O
Myriad	O
Group	O
and	O
UpOnTek	O
that	O
provide	O
Java	B-Language
ME	I-Language
to	O
Android	B-Application
conversion	O
services	O
.	O
</s>
<s>
Android	B-Application
provides	O
its	O
own	O
GUI	O
classes	O
,	O
and	O
does	O
not	O
provide	O
Java	B-Language
AWT	O
,	O
Swing	O
or	O
JavaFX	O
.	O
</s>
<s>
It	O
does	O
not	O
support	O
the	O
full	O
Java	B-Language
Beans	O
API	O
.	O
</s>
<s>
Android	B-Application
was	O
created	O
by	O
the	O
Open	O
Handset	O
Alliance	O
,	O
which	O
is	O
led	O
by	O
Google	O
.	O
</s>
<s>
The	O
early	O
feedback	O
on	O
developing	O
applications	O
for	O
the	O
Android	B-Application
platform	I-Application
was	O
mixed	O
.	O
</s>
<s>
Despite	O
this	O
,	O
Android-targeted	O
applications	O
began	O
to	O
appear	O
the	O
week	O
after	O
the	O
platform	O
was	O
announced	O
.	O
</s>
<s>
The	O
first	O
publicly	O
available	O
application	O
was	O
the	O
Snake	B-Application
game	I-Application
.	O
</s>
<s>
A	O
preview	O
release	O
of	O
the	O
Android	B-Application
SDK	I-Application
was	O
released	O
on	O
November	O
12	O
,	O
2007	O
.	O
</s>
<s>
On	O
July	O
15	O
,	O
2008	O
,	O
the	O
Android	B-Application
Developer	I-Application
Challenge	O
Team	O
accidentally	O
sent	O
an	O
email	O
to	O
all	O
entrants	O
in	O
the	O
Android	B-Application
Developer	I-Application
Challenge	O
announcing	O
that	O
a	O
new	O
release	O
of	O
the	O
SDK	O
was	O
available	O
in	O
a	O
"	O
private	O
"	O
download	O
area	O
.	O
</s>
<s>
The	O
email	O
was	O
intended	O
for	O
winners	O
of	O
the	O
first	O
round	O
of	O
the	O
Android	B-Application
Developer	I-Application
Challenge	O
.	O
</s>
<s>
The	O
revelation	O
that	O
Google	O
was	O
supplying	O
new	O
SDK	O
releases	O
to	O
some	O
developers	O
and	O
not	O
others	O
(	O
and	O
keeping	O
this	O
arrangement	O
private	O
)	O
led	O
to	O
widely	O
reported	O
frustration	O
within	O
the	O
Android	B-Application
developer	I-Application
community	O
at	O
the	O
time	O
.	O
</s>
<s>
On	O
August	O
18	O
,	O
2008	O
,	O
the	O
Android	B-Application
0.9	O
SDK	O
beta	O
was	O
released	O
.	O
</s>
<s>
On	O
September	O
23	O
,	O
2008	O
,	O
the	O
Android	B-Application
1.0	O
SDK	O
(	O
Release	O
1	O
)	O
was	O
released	O
.	O
</s>
<s>
On	O
December	O
5	O
,	O
2008	O
,	O
Google	O
announced	O
the	O
first	O
Android	B-Application
Dev	I-Application
Phone	I-Application
,	O
a	O
SIM-unlocked	O
and	O
hardware-unlocked	O
device	O
that	O
is	O
designed	O
for	O
advanced	O
developers	O
.	O
</s>
<s>
,	O
more	O
than	O
one	O
million	O
applications	O
have	O
been	O
developed	O
for	O
Android	B-Application
,	O
with	O
over	O
25	O
billion	O
downloads	O
.	O
</s>
<s>
Android	B-Application
smartphone	O
shipments	O
are	O
forecast	O
to	O
exceed	O
1.2	O
billion	O
units	O
in	O
2018	O
with	O
an	O
85%	O
market	O
share	O
.	O
</s>
